Embedded DfT Instrumentation: Design, Access, Retargeting and Case Studies

As semiconductor technologies enables highly advanced an complex integrated circuits (ICs), there is an increasing need to have more embedded design-for-test (DfT) instruments for test, debug, diagnosis, configuration, monitoring, etc. As these instruments are to be used not only at chip-level but also at board-level and system-level, a key challenge is how to access these instruments from chip terminals in a low-cost, non-intrusive, standardized, flexible and scalable manner. The well-adopted IEEE 1149.1 (Joint Test Action Group (JTAG)) standard offers low- cost, non- intrusive and standardized access but lacks flexibility and scalability, which is addressed by the on-going IEEE P1687 (Internal JTAG (IJTAG)) standardization initiative. We will discuss the need of embedded instrumentation, the shortcomings of IEEE 1149.1, the features and challenges of IEEE P1687, as well as cases studies on the usage of IEEE P1687